1. Field of the Invention
The present invention generally relates to a software facility for providing relatively seamless integration of "hypertext/hypermedia" services into existing, as well as new, computer program applications and, more particularly, to support for an end user interface, link and link marker authoring, link navigation and link marker abstracts, using an open system architecture. This includes support for the end user interface as well as storage in a database.
2. Definition of Terms
The following terminology is used throughout this disclosure.
Abstract: A text object consisting of keywords, phrases, and/or statements, which summarize the important information that would be found at a link marker with which the text object is associated.
Application: A computer program, other than an operating system, such as a word processor, spreadsheet, database management, graphics designer, and the like. As used herein, an application program is also referred to as a presenter.
Application Programming Interface (API): A means by which a program may call a service.
Client application: An application (presenter/program) which uses LMS services.
Context menu: Often referred to as "popup" menus, context menus are visually and functionally similar to pull-down menus, but are not tied to the action or command bar. They may appear at arbitrary positions in windows. Additionally, while the contents of a pull-down menu typically do not change based on the state of the application at any given time (though they may be enabled or disabled/grayed), the contents of a context menu, on the other hand, are dynamic, and change based on the state of the application; in other words, they are context sensitive. For instance, if a context menu contained an item which said, "Save", when the context menu is displayed and no data has been modified, the "Save" option would not appear in the menu. Context menus are typically displayed when the end user clicks a mouse button over some window. Context menus typically contain similar function to pull-down menus, but only include those items which are relevant to the object clicked on, at a given time.
Document: A named set of data (such as a text file, an image file, a video passage, etc.) usually, but not necessarily, discernible by an end user (when rendered by a presenter). Thus, the term "document" is not limited to a text file but may be text, bitmap graphics, a spreadsheet or some other data presentation. In some cases, other objects are considered as "documents" by LMS. These objects include audio files, motion video files and clips, and a series of image files (i.e., slide shows).
End User Interface (EUI): The methodology, including devices, by which an end user interacts with a system, system component, and/or system application.
Graphical User Interface (GUI): An EUI which is graphical; for example, end user interactions with the system via windows, icons, menus, pointing devices, etc.
Hypertext/Hypermedia: In the generic and simplest sense, these terms mean touch and get. They embody the notion of an end user being able to touch (e.g., using some kind of pointing device) an object (e.g., a word, phrase, graphical object, etc.) and thereby cause one or more associated information entities to be obtained. A survey of hypertext systems is provided in "Hypertext: An Introduction Survey" by Jeff Conklin, IEEE Computer, September 1987, pp. 17-41, and "An Overview of Hypertext and Hypermedia", Concepts & Issues, McGraw-Hill, November 1989.
Link: An object which associates a point in one document with a point in another document (or different point in the same document). Links may be bidirectional and therefore may be followed from either end.
Link Manager Services (LMS): A complete integrated set of hypertext/hypermedia services.
Link marker: A (typically) visual indication to the end user, contained within a document, indicating that there may be one or more links present at this point (the link marker's location) in the document. If there are links emanating from a link marker and the link marker is triggered (e.g., by the end user with a mouse), the link marker's links may be navigated. LMS provides link markers that can have many different appearance styles, including (1) push-buttons which may optionally contain text, (2) black frames which allow the end user to see through the link marker's framed area to the client application's underlying rendered data, (3) highlight frames which, like black frames, provide for transparency, but which have frames which are guaranteed to be visible (particularly useful compared to black frames when some of the underlying data may be black or very dark), (4) highlight areas which are also transparent in that the patterns of the underlying data will be discernible, but the colors of the underlying data will be changed (also sometimes known as reverse video, e.g., all underlying black color is changed to white, all white color is changed to black, all blue color is changed to yellow, etc.), and (5) invisible which are truly invisible with regard to any occlusion of the underlying data.
Mouse: The term mouse, when used in this document, really refers to any type of operating system supported pointing device including, but not limited to a mouse, track ball, lightpen, touch screen, and the like. Also, the screens, keyboard and mouse operations, menus, etc. with which an end-user interacts with when using an application.
Navigation: The following, or traversal, of a link.
Open system: A hypermedia system which allows any application (presenter) to participate in linking. Such applications need not be aware of documents and/or presenters at the other ends of links, thus allowing for the seamless integration of applications and application-rendered data developed totally independently from one another.
Presenter: An application which renders data (e.g., text files, image files, audio passages, etc.) for an end user.
Pull-down menu: These are the menus which are tied to the action bar (menu bar) at the top of a window. These menus may also contain submenus, which are known as cascade menus.
2. Description of the Prior Art
A number of hypertext/hypermedia systems are programmed in an object-oriented programming language, such as Smalltalk and C++. The former was developed at the Xerox Palo Alto Research Center (PARC), and a good description of that language may be had by reference to the textbook by Adele Goldberg and David Robson entitled Smalltalk-80: The Language and Its Implementation, Addison-Wesley, 1983. The C++ language was developed by Bjarne Stroustrup of AT&T Bell Laboratories and described, for example, in his book entitled The C++ Programming Language, Addison-Wesley, 1986. Among the advantages of Object-Oriented Programming Systems (OOPS) are modular structure and object-oriented user interfaces using icons. Further information on object oriented programming and hypersystems may be obtained from "Design and Use of Hyperdedia Systems" by Robert Akscyn of Knowledge Systems, Inc., Conference on Human Factors in Computing Systems, May 14, 1988, and "Intermedia: The Architecture and Construction of An Object Oriented Hypermedia System and Application Framework" by Norman Meyrowitz, IRIS, Brown University, OOPSLA Proceedings, September 1986.
Insofar as the inventors are aware, there are no hypertext/hypermedia systems, or system services, which enable applications (presenters) to seamlessly and easily incorporate hypertext/hypermedia capabilities in an open system architecture, as well as automatically provide a consistent end user hypermedia interface which is managed by the hypermedia services, and not the presenter itself. Additionally, even those hypermedia systems which are somewhat "open" systems cannot alter the user interface upon future releases without requiring all hypermedia applications in the system to be modified and rebuilt.
The prior art discussed below are representative of products and/or services which implement hypertext/hypermedia capabilities.
HyperCard published by Apple Corp. is considered by many (including its author, Bill Atkinson) to not be a hypermedia product, but rather an "application builder" or "stack of cards". When viewed as a hypermedia system (in that cards are "linked" together) it is a closed hypermedia system; e.g., one must use only the presentation facilities supplied by the product. HyperCard provides no facility for enabling other (non-HyperCard-supplied) applications (presenters) with hypermedia capabilities.
The SuperCard program by Silicon Beach Software is a HyperCard "look-alike", with more power than HyperCard. It provides stacks of "cards", as well as application generation. Other examples of closed hypermedia systems include Guide 2.0 by OWL International, Inc. which provides no facility for enabling other (nonGuide-supplied) applications (presenters) with hypermedia capabilities; IRIS Intermedia by Institute for Research in Information and Scholarship (IRIS), Brown University, which also provides no facility for enabling other (non-Intermedia-supplied) applications (presenters) with hypermedia capabilities; and LinkWay 2.0 by IBM Educational Systems and which provides no facility for enabling other (non-LinkWay-supplied) applications (presenters) with hypermedia capabilities.
Sun Link Service by Sun Microsystems is the only other open hypermedia system known to the inventors as an available product. Sun's facility does provide a set of services which allow other (non-Sun-supplied) applications to be enabled with hypermedia capabilities; however, this enablement is neither seamless nor easy. Additionally, the Sun Link Service does not manage the end user interface for the hypermedia capabilities, which means that each application must implement its own notion in that regard. Additional information on this product may be found in an article entitled "Sun's Link Service: A Protocol for Open Linking" by Amy Pearl on pages 137-146 of the Hypertext-'89 Proceedings.
In addition to the foregoing, several other products which implement hypertext/hypermedia capabilities were reviewed in the October 1990 issue of PC/Computing Magazine at pages 201-210. These include Folio Views 2.0 by Folio Corp., Hyperties by Cognetics Corp., HyperWriter by Ntergaid, Spinnaker Plus 2.0 by Spinnaker Software Corp., and Transtext by MaxThink. Folio Views was reviewed as: "An information management system that lets you compress large text files into a customized `infobase` and create cross-referencing links." Nothing further is known of this product, however, the review suggests that this would not allow for linking between different presenters and/or different types of data. This also suggests that no method is provided for enabling other (non-Folio Views-supplied) applications (presenters) with hypermedia capabilities.
Hyperties was reviewed as: "An interactive system that lets you create hypertext documents and manuals from a variety of media, including existing files, online information, scanned material and video." Hyperties is a closed hypermedia system; e.g., one must use only the presentation facilities supplied by the product. Nothing further is known of this product, however, the review suggests that no method is provided for enabling other (non-Hyperties-supplied) applications (presenters) with hypermedia capabilities.
HyperWriter was reviewed as: "A hypertext authoring tool with audio and video capabilities and a limited scripting language."
Spinnaker Plus 2.0 was reviewed as :"A hypertext programming environment for developing and running custom information management applications." Although no more information than this is known, it appears from the review that Spinnaker is more of an application generator program than a "true" hypertext product.
Transtext was reviewed as: "A word processor that lets you create hypertext links to many other commercially available applications." Nothing further is known of this product, however, the review seems to indicate that unidirectional links out of the product may be established, which probably simply cause the launching of existing commercially available applications, simply passing them user-specified parameters.
In addition, KnowledgePro by Knowledge Garden, Inc., was reviewed in the November 1989 issue of Concepts & Issues, referenced above, as: ". . . while some skill in programming is useful in becoming familiar with the product, its developers claim such skill is not a prerequisite to learning the program . . . a programming environment that combines an expert system generator with hypertext . . . It can read external files, call external programs, and be extended by routines written in other languages." In addition, the review also suggests that the programming environment/expert system generator combination could yield some sophisticated searching capabilities. However, nothing more specific is known either about the search capabilities or the degree of openness contained in the product.